electrolyte

It may not be particularly useful to create some makeshift batteries out of soda and soda cans, but it’s a good introduction to electrodes and electrolytes as well as a welcomed break from lemons and potatoes. The gang at [Go-Repairs] lopped off the can’s lid and temporarily set the soda aside, then took steel wool to the interior of the can to remove the protective plastic coating. The process can be accelerated by grabbing your drill and cramming the steel wool onto the end of a spade bit, although pressing too hard might rip through the can.

With the soda poured back in, you can eek out some voltage by clipping one lead to the can and another to a copper coin that’s dunked into the soda. Stringing along additional cans in series can scale up the juice, but you’ll need a whole six pack before you can get an LED working—and only just. The instructions suggest swapping out the soda for a different electrolyte: drain cleaner, which can pump out an impressive 12 volts from a six pack series. You’ll want to be careful, however, as it’s likely to eat through the can and is one lid away from being dangerous.

This one would make a nice centerpiece for your Halloween party. It’s a battery with tiny pumpkins serving as the cells. [EM Daniels] shows us how to clear out the pumpkins, fill them with some freshly mixed electrolyte, and he even throws in the directions for baking the pumpkin seeds.

Each pumpkin will need a pair of conductors made of dissimilar metals to serve as the anode and cathode. Copper wire is used for one, aluminum for the other, and both wires have a spiral pattern bent on one end to increase the surface area that contacts the electrolytic solution. Now just boil up a slurry of vinegar, gelatin, and salt, then let it sit in the fridge over night. [EM Daniels] was able get 1.5V out of this project (enough to light one LED) for two hours, and 1.4V for six hours by using seven of the pumpkin cells in series.